1. Field of the Invention
The present invention relates to an active headrest apparatus for a vehicle and an actuator thereof
2. Description of Related Art
A vehicle headrest is installed on the top of the back of a vehicle seat to support the head and neck of an occupant. The vehicle headrest prevents the head and neck of the occupant from being injured by the backlash of the body during a collision and ensures a comfortable ride by supporting the head and neck of an occupant under normal driving conditions.
As shown in FIG. 6, the active headrest apparatus of the prior art includes a seat frame 20, a rotational shaft 40 rotatably installed inside the seat frame 20, a shock suspension 50 connected to the rotational shaft 40 and rotatably installed around the rotational shaft 40 inside the seat frame 20, a headrest 10 located on the top of the seat frame 20, and connecting rods 30 extending through guide holes formed in the top portion of the seat frame 20 to link the shock suspension 50 with the headrest 10.
In the conventional active headrest apparatus, the headrest is moved up and forward at the same time by a crash test dummy during a rear-end collision and then moves back to the initial position without maintaining the position moved to when the dummy moved forwards. On the other hand, the upper body of the occupant is instantaneously pushed forward by a seatback and the neck of the occupant performs a relative motion with respect to the upper body because of the inertial force. Like this, the relative motion of the neck may apply considerable pressure to the neck joint and the soft tissues around the neck.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.